Users can provide inputs to electronic devices using many different approaches. In some cases, an electronic device can include a dome switch, which can be actuated to provide a detectable input. The dome switch can be constructed by placing a conductive dome over a contact pad of a circuit board. When the dome is pressed, the dome can invert such that an inner surface of the dome contacts the contact pad. A volume of air enclosed between the dome and the circuit board may be expelled from the dome when the dome is depressed, for example through vents of the dome switch. The vents however, may also allow foreign contaminants or particles to enter the volume enclosed between the inner surface of the dome and the circuit board. The foreign contaminants or particles can adversely affect the operation of the dome switch by causing rust, oxidation, dendrite growth, or deposits of foreign substances.